Pounds to stone converter

Pounds are often used on parcel labels and equipment specifications. This is avoirdupois mass, rather than a force rating. If the source gives pounds plus ounces, combine them correctly before conversion. A carrier's billed weight can also depend on package dimensions.

One pound is about 0.0714285714 stone. The international avoirdupois pound is defined as exactly 0.45359237 kg (1959 agreement).

Multiply the number of pounds by 0.0714285714. For example, 154 lb × 0.0714285714 = 11 st. To go the other way, divide by 0.0714285714.

Multiply by 0.07. That is 2% low of the exact factor 0.0714285714, so 154 lb comes out as 10.78 st instead of 11.

Accuracy depends on your inputs and the method's assumptions. Decimal arithmetic uses 50 significant digits, but estimates, numerical methods and source data can be less precise; the displayed rounding does not remove those limits. It is checked against 3 worked examples whose answers come from independent sources; for example, “154 lb to st” is checked against Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions).

NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B; NIST Handbook 44, Appendix C: General tables of units of measurement; BIPM, The International System of Units (SI Brochure), 9th edition.